The feasibility of using oxygen-enriched air to increase the power of intake-port hydrogen injection internal combustion engine was verified by experiments. Hydrogen-air prototyping tests and 30%, 40% intake oxygen concentration tests were conducted. Based on these data, the one-dimensional simulation model of engine was built and calibrated. The results show that the power increases by 20.5% and the brake thermal efficiency decreases by 2% on average when the equivalence ratio is 0.7 and the intake oxygen concentration increases to 30%. The power increases by 36.5% and the thermal efficiency decreases by 4% when the intake oxygen concentration increases to 40%. The results can guide the future tests of engine with higher intake oxygen concentration and provide a new method for improving the power of intake-port hydrogen injection internal combustion engine.